The Sun activity increases during every ...
5 years
11 years
22 years
1300 years
Solar cycles have an average duration of about 11 years. The periodic changes in the Sun's activity include changes of the levels of solar radiation and the number and size of sunspots.
reach: rather globalastronomySununiverse
Answers by country
5 years
11 years
22 years
1300 years
answers

20

76

20

10

12

12

425

24

21

247

129

35

44

383

8206

15

32

16

10